PURPOSE: Candida albicans (C. albicans) and Proteus species are causative agents in a variety of opportunistic nosocomial infections, and their ability to form biofilms is known to be a virulence factor. In this study, the influence of co-cultivation with Proteus vulgaris (P. vulgaris) and Proteus mirabilis (P. mirabilis) on C. albicans biofilm formation and its underlying mechanisms were examined. MATERIALS AND METHODS: XTT reduction assays were adopted to measure biofilm formation, and viable colony counts were performed to quantify yeast growth. Real-time reverse transcriptase polymerase chain reaction was used to evaluate the expression of yeast-specific genes (rhd1 and rbe1), filament formation inhibiting genes (tup1 and nrg1), and hyphae-related genes (als3, ece1, hwp1, and sap5). RESULTS: Candida biofilm formation was markedly inhibited by treatment with either living or heat-killed P. vulgaris and P. mirabilis. Proteus-cultured supernatant also inhibited Candida biofilm formation. Likewise, treatment with live P. vulgaris or P. mirabilis or with Proteus-cultured supernatant decreased expression of hyphae-related C. albicans genes, while the expression of yeast-specific genes and the filament formation inhibiting genes of C. albicans were increased. Heat-killed P. vulgaris and P. mirabilis treatment, however, did not affect the expression of C. albicans morphology-related genes. CONCLUSION: These results suggest that secretory products from P. vulgaris and P. mirabilis regulate the expression of genes related to morphologic changes in C. albicans such that transition from the yeast form to the hyphal form can be inhibited.
Biofilms* ; Candida albicans* ; Candida* ; Cross Infection ; Mirabilis ; Proteus mirabilis* ; Proteus vulgaris* ; Proteus* ; Reverse Transcriptase Polymerase Chain Reaction ; Virulence ; Yeasts

The purpose of this study is to investigate the correlation of cell surface hydrophobicity (CSH) and biofilm formation or adhesion in Candida albicans (C. albicans) and several pathogenic bacteria. All of C. albicans (n=82) and 7 bacterial species (Escherichia coli, n=25; Klebsiella pneumoniae, n=33; Morganella morganii, n=21; Proteus mirabilis, n=33; Proteus vulgaris, n=12; Pseudomonas aeruginosa, n=31; Staphylococcus aureus, n=31) were isolated clinically. CSH was quantified with microbial adhesion to hydrocarbons. Biofilm formation was determined by tetrazolium salt reduction assay. Adhesion assay was performed by counting colonies after culture the microbes adhered to HeLa cells. Although high CSH-expressing bacterial species showed greater adherence to HeLa cells and larger amounts of biofilm formation on polystyrene, the significant relationships within same species were not shown. In C. albicans, however, strong positive correlations were observed between CSH and biofilm formation (r =0.708; p < 0.05) or cell adhesion (r =0.509; p < 0.05). These results suggest that hydrophobic force of bacteria may play a minor role in adhesion and biofilm formation, but CSH of C. albicans may be an important factor for adherence on surface and biofilm forming process.
Bacteria ; Biofilms* ; Candida albicans* ; Candida* ; Cell Adhesion ; HeLa Cells ; Humans ; Hydrocarbons ; Hydrophobic and Hydrophilic Interactions* ; Klebsiella pneumoniae ; Morganella morganii ; Polystyrenes ; Proteus mirabilis ; Proteus vulgaris ; Pseudomonas aeruginosa ; Staphylococcus aureus

BACKGROUND: At antimicrobial susceptibility testing (AST), clinical isolates may appear susceptible sometimes to the antibiotics that are clinically ineffective or due to technical errors in the testing. So an interpretive reading of AST should be done, but most hospitals do not perform it routinely. Here, we developed and evaluated a computerized expert system to interpret AST of Enterobacteriaceae to beta-lactam antibiotics. METHODS: We made a rule-based expert system according to the natural resistance of the members of Enterobacteriaceae and the common phenotypes of resistance mechanisms for Enterobacteriacae. Antimicrobial suceptibility testings were performed using the disk diffusion method with 12 beta-lactam antibiotics for a total of 1, 016 clinical isolates. Then we compared the raw and expert results of AST. RESULTS: An overall discrepancy rate due to natural resistance was 5.9%; 10.4% for Klebsiella spp. and Citrobacter diversus, 15.0% for Enterobacter spp., 2.6% for Serratia marcescens, 31.6% for Morganella morganii and Providencia stuartti. Accoriding to acquired antimicrobial resistant mechanisms, overall resistant discrepancy was 21.8%; 18.8% for Escherichia coli, Proteus mirabilis, Salmonella and Shigella spp., 25.9% for Citrobacter diversus and Klebsiella spp., 21.6% for Citrobacter freundii and Enterobacter spp., 45.6% for Morganella morganii, 10.0% for Proteus vulgaris, 12.2% for Serratia spp.. CONCLUSIONS: These results indicate that the application of the expert system for interpretation of antimicrobial susceptibility test may provide more reliable data for the treating physician. Additional information should be applied on the software for new resistant mechanisms or some misinterpretive readings.
Anti-Bacterial Agents ; beta-Lactams* ; Citrobacter freundii ; Citrobacter koseri ; Diffusion ; Enterobacter ; Enterobacteriaceae* ; Escherichia coli ; Expert Systems* ; Immunity, Innate ; Klebsiella ; Morganella morganii ; Phenotype ; Proteus mirabilis ; Proteus vulgaris ; Providencia ; Reading ; Salmonella ; Serratia ; Serratia marcescens ; Shigella

Contamination with sanitary microorganisms from Enterobacteriaceae, Pseudomonadaceae, Staphylococcaceae, Micrococcaceae and Bacillaceae families in flower bee pollen from Bulgaria after one-year vacuum-packed cold storage has been found. Dried flower bee pollens intended for human consumption were with high incidence rate of contamination with Pantoea sp. (P. agglomerans and P. agglomerans bgp6) (100%), Citrobacter freundii (47%), Proteus mirabilis (31.6%), Serratia odorifera (15.8%) and Proteus vulgaris (5.3%). Bee pollens were also positive for the culture of microorganisms from Staphylococcaceae, Micrococcaceae and Bacillaceae families: Staphylococcus hominis subsp hominis, Staphylococcus epidermidis, Arthrobacter globiformis, Bacillus pumilis, Bacillus subtilis and Bacillus amyloliquefaciens. It was concluded that, if consumed directly, the vacuum-packed cold stored dried bee pollen, harvested according hygienic requirements from bee hives in industrial pollution-free areas without intensive crop production, is not problem for healthy human.
Arthrobacter ; Bacillaceae ; Bacillus ; Bacillus subtilis ; Bees* ; Bulgaria ; Citrobacter freundii ; Crop Production ; Enterobacteriaceae ; Flowers* ; Humans ; Incidence ; Micrococcaceae ; Pantoea ; Pollen* ; Proteus mirabilis ; Proteus vulgaris ; Pseudomonadaceae ; Serratia ; Staphylococcaceae ; Staphylococcus epidermidis ; Staphylococcus hominis ; Urticaria ; Vacuum*

No abstract available.
Candida albicans* ; Candida* ; Ecthyma* ; Giant Lymph Node Hyperplasia* ; Humans ; Proteus vulgaris* ; Proteus*

Pyogenic liver abscess causes various clinical manifestations and resulted in complications in 30-50 % of cases. Pericarditis due to pyogenic liver abscess is a very rare complication, the result of which is usually fatal without treatment. We report a case of 60-year-old female who had pyogenic liver abscess by Proteus vulgaris complicated with acute purulent pericarditis. Another 3 cases in previous Korean literature were also reviewed.
Female ; Humans ; Liver Abscess, Pyogenic* ; Middle Aged ; Pericarditis* ; Proteus vulgaris* ; Proteus*

Pyogenic liver abscess causes various clinical manifestations and resulted in complications in 30-50 % of cases. Pericarditis due to pyogenic liver abscess is a very rare complication, the result of which is usually fatal without treatment. We report a case of 60-year-old female who had pyogenic liver abscess by Proteus vulgaris complicated with acute purulent pericarditis. Another 3 cases in previous Korean literature were also reviewed.
Female ; Humans ; Liver Abscess, Pyogenic* ; Middle Aged ; Pericarditis* ; Proteus vulgaris* ; Proteus*

High cholesterol is one of the important factors inducing cardiovascular and cerebrovascular diseases. Drug therapy is the main method for reducing cholesterol, but has the disadvantages such as high cost and side effects. Studies have shown that intestinal bacteria play important roles in cholesterol metabolism. However, there are few reports on the screening and functional evaluation of cholesterol-lowering intestinal bacteria. In this study, 36 bile-tolerant bacteria were screened from healthy people stool through culturomics using bovine bile acid or artificial mixed bile acids as substrates. Taking Lactobacillus rhamnosus GG (LGG) as a positive control, three bile acid concentration groups (0 g/L, 0.3 g/L, 3 g/L) were set up to evaluate the cholesterol-lowering ability of bile-tolerant bacteria in vitro. Ten bacteria (including Proteus mirabilis, Providencia stuartii, Proteus vulgaris et al) were identified as the dominant cholesterol-lowering bacteria. Six of the above bacteria, Proteus mirabilis, Providencia stuartii, Proteus vulgaris, Proteus penneri, Wohlfahrtiimonas chitiniclastica, Providencia rettger, were evaluated for their ability to reduce triglycerides in vitro and tolerance to artificial gastric juice. Comparing with strain LGG, the six bacteria showed better triglyceride-lowering ability in vitro. With the decrease of pH value of artificial gastric juice and the increase of treatment time, the survival rate of six bacteria decreased. The above screening experiments and functional evaluation provide a basis for further development of potential cholesterol-lowering bacterial products.
Animals ; Cattle ; Cholesterol ; Gammaproteobacteria ; Humans ; Proteus mirabilis ; Providencia

OBJECTIVE: To construct a modABC gene knockout strain of Proteus mirabilis and explore the effect of modABC gene deletion on biological characteristics of Proteus mirabilis. METHODS: Fusion PCR was used to obtain the fusion gene of modABC and the kanamycin-resistant gene Kn, which was ligated with the suicide vector pCVD442 and transduced into Proteus mirabilis. The modABC gene knockout strain of Proteus mirabilis was obtained after homologous recombination with the suicide vector. PCR and Sanger sequencing were used to identify genomic deletion of modABC gene in the genetically modified strain. The concentration of molybdate in the wild-type and gene knockout strains was determined using inductively coupled plasma mass spectrometry (ICP-MS), and their survival ability in LB medium was compared under both aerobic and anaerobic conditions. RESULTS: PCR and sanger sequencing confirmed genomic deletion of modABC gene in the obtained Proteus mirabilis strain. The concentration of intracellular molybdenum in the modABC gene knockout strain was 1.22 mg/kg, significantly lower than that in the wild-type strain (1.46 mg/kg, P < 0.001). Under the aerobic condition, the modABC gene knockout strain grown in LB medium showed no significant changes in survival ability compared with the wild-type strain, but its proliferation rate decreased significantly under the anaerobic condition and also when cultured in nitrate-containing LB medium under anaerobic condition. CONCLUSION Homologous recombination with the suicide vector can be used for modABC gene knockout in Proteus mirabilis. modABC gene participates in molybdate uptake and is associated with anaerobic growth of Proteus mirabilis in the presence of nitrate.
Humans ; Gene Deletion ; Nitrates ; Proteus mirabilis/genetics* ; Gene Knockout Techniques

BACKGROUND: Accurate detection of extended spectrum beta-lactamase (ESBL) is important because ESBLproducing organisms may appear susceptible to oxyimino- beta-lactams in standard susceptibility tests, but are considered to be clinically resistant to these drugs. And continued monitoring of isolation trend of ESBL-producing organisms is essential for the guideline settlement of antibiotic usage and infection control program. METHODS: Disk diffusion test using the Clinical and Laboratory Standards Institute's ESBL phenotypic confirmatory test were performed on 5,511 clinical isolates of Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, and Proteus mirabilis during the recent six years (April 2001-March 2007). The ESBL producer was defined as an organism showing an increase in the zone diameter of > or =5 mm for either cefotaxime or ceftazidime with clavulanic acid versus that without clavulanic acid (CTC confirmatory test, CZC confirmatory test, respectively). RESULTS: The ESBL-positive rates were 34.8% in K. pneumoniae, 9.3% in K. oxytoca, 8.4% in E. coli, and 6.5% in P. mirabilis. Among the ESBL-positive organisms, the detection rates of ESBL CTC and CZC confirmatory tests were as follows: 91.3% vs 68.7% in K. pneumoniae, 96.3% vs 44.4% in K. oxytoca, 94.8% vs 45.4% in E. coli, and 100% vs 20% in P. mirabilis. ESBL-producing K. pneumoniae had shown a continuously increasing trend from 24.3% in 2001 to 46.4% in 2006. CONCLUSION: Both of the ESBL confirmatory tests should be simultaneously tested for the accurate detection of ESBL-producing K. pneumoniae, K. oxytoca, E. coli, and P. mirabilis. In addition, an active infection control approach is needed for ESBL-producing K. pneumoniae.
beta-Lactamases* ; beta-Lactams ; Cefotaxime ; Ceftazidime ; Clavulanic Acid ; Diffusion ; Escherichia coli* ; Escherichia* ; Infection Control ; Klebsiella oxytoca ; Klebsiella pneumoniae ; Klebsiella* ; Mirabilis ; Pneumonia ; Proteus mirabilis* ; Proteus*